416 Mr. Gill on the Intensity of the Ultra-Violet Light 



The most interesting result of the experiments is, however, 

 the systematic variation with the pressure. In fig. 2 starting 



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with the higher pressures the greater part of the light comes 

 from the left end, that is the end nearer the anode, the 

 amount from the centre being small; the same is true for 

 the slightly lower pressure in fig. 3, the fact that the maximum 

 is a little higher than in fig. 2 is probably due to errors of 

 experiment. In fig. 4, although the general features are 

 still the same, the right-hand maximum is beginning to 

 become more prominent. 



